Alert archive / New Jersey / Severe Thunderstorm Warnings in 2024

Severe Thunderstorm Warning 210, NWS Philadelphia/Mount Holly

August 18, 2024Morris County, Sussex County, New Jersey

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 18, 2024, 5:47 PM EDT for Morris County, Sussex County, New Jersey. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 18, 2024, 5:47 PM EDT (21:47 UTC)
Expired
Aug 18, 2024, 6:30 PM EDT
In force
43 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Morris County, NJ, Sussex County, NJ

The radar

The Philadelphia radar (KDIX), 118 km from the middle of the area, began a volume at 21:48 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Aug 18, 2:02 PM EDTSevere Thunderstorm WatchSPC8 hr

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.8 hours before the alert went out and 131 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2024-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 109 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2024-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 187 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
109 J/kg
Mixed-layer CIN
-20 J/kg
Mixed-layer LCL
582 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
187 m²/s²
0-3 km storm-relative helicity
205 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted.

251 
WUUS51 KPHI 182147
SVRPHI
NJC027-037-182230-
/O.NEW.KPHI.SV.W.0210.240818T2147Z-240818T2230Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
547 PM EDT Sun Aug 18 2024

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Northeastern Morris County in northern New Jersey...
  Southeastern Sussex County in northwestern New Jersey...

* Until 630 PM EDT.

* At 547 PM EDT, a severe thunderstorm was located over Lake
  Telemark, or 11 miles southwest of West Milford, moving east at 20
  mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Morristown, Dover, Hopatcong, East Hanover, Lincoln Park, Kinnelon,
  Boonton, Butler, Wharton, Rockaway, Morris Plains, Mount Arlington,
  Franklin, Mountain Lakes, Riverdale, Hamburg, Ogdensburg, Victory
  Gardens, Lake Mohawk, and Green Pond.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 30 and 49.
 Interstate 287 in New Jersey between mile markers 39 and 54.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather, contact your nearest law enforcement
agency. They will send your report to the National Weather Service
office in Mount Holly NJ.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4120 7436 4110 7449 4104 7450 4105 7445
      4102 7443 4103 7442 4100 7430 4097 7428
      4092 7429 4090 7427 4091 7434 4086 7432
      4082 7434 4080 7462 4112 7471 4124 7444
TIME...MOT...LOC 2147Z 254DEG 19KT 4098 7454 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS
2 follow-up statements
771 
WWUS51 KPHI 182219
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
619 PM EDT Sun Aug 18 2024

NJC037-182229-
/O.CAN.KPHI.SV.W.0210.000000T0000Z-240818T2230Z/
Sussex NJ-
619 PM EDT Sun Aug 18 2024

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SUSSEX COUNTY IS
CANCELLED...

The severe thunderstorm which prompted the warning has moved out of 
the warned area. Therefore, the warning has been cancelled.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
northern New Jersey.

LAT...LON 4081 7447 4105 7447 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4092 7429
      4090 7427 4091 7434 4086 7432 4082 7434
TIME...MOT...LOC 2219Z 265DEG 16KT 4097 7437 

$$

NJC027-182230-
/O.CON.KPHI.SV.W.0210.000000T0000Z-240818T2230Z/
Morris NJ-
619 PM EDT Sun Aug 18 2024

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 630 PM EDT
FOR NORTHEASTERN MORRIS COUNTY...

At 619 PM EDT, a severe thunderstorm was located over Kinnelon, or
near Pompton Lakes, moving east at 20 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
East Hanover, Lincoln Park, Kinnelon, Boonton, Butler, Morris Plains,
Mountain Lakes, Riverdale, Parsippany, Pequannock Township, and
Hanover Township.

This includes the following highways...
 Interstate 80 in New Jersey between mile markers 41 and 49.
 Interstate 287 in New Jersey between mile markers 39 and 54.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

To report severe weather contact your nearest law enforcement agency.
They will send your report to the National Weather Service office in
Mount Holly NJ.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4081 7447 4105 7447 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4092 7429
      4090 7427 4091 7434 4086 7432 4082 7434
TIME...MOT...LOC 2219Z 265DEG 16KT 4097 7437 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...0.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

MPS
828 
WWUS51 KPHI 182226
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
626 PM EDT Sun Aug 18 2024

NJC027-182236-
/O.EXP.KPHI.SV.W.0210.000000T0000Z-240818T2230Z/
Morris NJ-
626 PM EDT Sun Aug 18 2024

...THE SEVERE THUNDERSTORM WARNING FOR NORTHEASTERN MORRIS COUNTY
WILL EXPIRE AT 630 PM EDT...

The storm which prompted the warning has weakened below severe
limits, and has exited the warned area. Therefore, the warning will
be allowed to expire.

A Severe Thunderstorm Watch remains in effect until 1000 PM EDT for
northern New Jersey.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 4081 7447 4105 7447 4105 7445 4102 7443
      4103 7442 4100 7430 4097 7428 4092 7429
      4090 7427 4091 7434 4086 7432 4082 7434
TIME...MOT...LOC 2226Z 254DEG 19KT 4098 7433 

$$

MPS

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 18, 3:09 AM EDTFlash Flood WarningPHIBurlington, Camden93 min
Aug 18, 4:41 AM EDTFlash Flood WarningPHIBurlington, Camden, Mercer2 hr
Aug 18, 2:17 PM EDTSpecial Marine WarningPHI58 min
Aug 18, 2:42 PM EDTSpecial Marine WarningPHI93 min
Aug 18, 3:55 PM EDTSpecial Marine WarningPHI95 min
Aug 18, 4:04 PM EDTSevere Thunderstorm WarningPHIWarren41 min
Aug 18, 4:41 PM EDTSevere Thunderstorm WarningPHISussex, Warren34 min
Aug 18, 4:56 PM EDTFlash Flood WarningPHIWarren6 hr
Aug 18, 5:10 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Warren29 min
Aug 18, 5:21 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden39 min
Aug 18, 5:31 PM EDTFlash Flood WarningPHIHunterdon, Warren6 hr
Aug 18, 5:38 PM EDTFlash Flood WarningPHISussex, Warren4 hr
Aug 18, 5:47 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth58 min
Aug 18, 5:51 PM EDTSevere Thunderstorm WarningPHIMorris, Somerset24 min
Aug 18, 5:59 PM EDTSevere Thunderstorm WarningPHIMorris, Sussex18 min
Aug 18, 6:01 PM EDTFlash Flood WarningPHIHunterdon, Morris, Somerset, Sussex, Warren6 hr
Aug 18, 6:24 PM EDTSevere Thunderstorm WarningPHIMiddlesex, Morris, Somerset66 min
Aug 18, 6:36 PM EDTFlash Flood WarningPHIMorris, Somerset5 hr

Nearby

Severe Thunderstorm Warnings in New Jersey, 2024Every severe thunderstorm warning in 2024

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.